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Background This study analyzes the incidence of microembolic infarctions (MIs) in the cerebellum after carotid artery stenting (CAS) to determine the risk factors. Methods From 2012 to 2019, 162 CASs in 155 patients were performed at our hospital. Fifty-seven patients (35.7%) showing new MIs on diffusion-weighted imaging after CAS were enrolled. Patients were assigned to either the cerebellar group (n = 14, 8.8%) if their MIs were in the cerebellum and/or cerebrum or the cerebral group (n = 43, 26.9%) if their MIs were only in the cerebrum. Patient characteristics, anatomic features, and clinical data were retrospectively compared between the 2 groups. Results Advanced age, right-sided carotid stenosis, severe calcification of aortic arch and brachiocephalic trunk, and vertebral artery narrowing with intraprocedural hemodynamic depression (IHD) significantly increased the development of cerebellar MIs. On multivariate analysis, advanced age, right-sided carotid stenosis, and vertebral artery narrowing with IHD were independent predictors of developing new cerebellar MIs. Cerebellar MIs after CAS were not uncommon. Conclusions Catheter maneuvering in the aortic arch or the brachiocephalic trunk could be the main cause of thromboemboli in cerebellar MIs. Careful attention should be paid to catheter maneuvering, especially in older patients with right-sided carotid lesions. In addition, cerebellar hypoperfusion caused by vertebral artery narrowing with IHD might reduce washout of debris, a cause of cerebellar MIs.

Background Malignant gliomas are characterized by high invasive ability. In this study, we investigated roles of layilin, a C-type lectin-homologous protein, in the invasive ability of malignant glioma cells. Methods Expression of layilin was investigated by western blotting in the malignant glioma cell lines of U251-MG, A172, and T98G and in astrocytes. The effects of layilin-knockdown on the expression and protein levels of snail family transcriptional repressor 1 (SNAI1), a transcriptional factor involved in the acquisition and enhancement of invasive ability in malignant gliomas, and on the expression of its target genes, matrix metalloproteinase 2 (MMP2), MMP9, and collagen type I alpha 1 chain (COL1A1), were investigated by qPCR and/or western blotting. Furthermore, the effects of layilin-knockdown on the expression and protein levels of metastasis associated 1 family member 3 (MTA3), a transcriptional repressor of SNAI1, were also investigated by qPCR and western blotting. Finally, the effects of layilin-knockdown on the invasive ability of the cells were investigated by a wound healing assay. Results All the tested malignant glioma cells highly expressed layilin, compared to astrocytes, one of representative glial cell types. Layilin-knockdown reduced SNAI1 both at the mRNA and protein levels in A172 cells, and consequently mRNA levels of MMP2, MMP9, and COL1A1 were also reduced. Furthermore, layilin-knockdown increased nuclear protein levels of MTA3 in A172 cells. Notably, layilin-knockdown suppressed the invasive ability of the cells. Conclusion Layilin up-regulates the expression of SNAI1 via down-regulation of MTA3. This process enhances the invasive ability of malignant glioma cells.

We demonstrate high harmonic generation from GaSe in the deep-UV range with its photon energy reaching three times the bandgap energy. The harmonic spectrum represents a clear dependence on the crystal orientation with respect to the incident field, reflecting the 6 ¯ 2 m point group. This reflection indicates the possibilities of high harmonic spectroscopy and high harmonic waveform control at frequencies well above the bandgap. The 3D time-dependent density matrix simulations reveal that the interband polarization mechanism dominates over the intraband current mechanism at frequencies above the bandgap and can generate attosecond bursts with characteristic sine-like waveforms.

Targeted protein degradation (TPD) through a proteasome-dependent pathway induced by heterofunctional small molecules is initiated by the formation of a ternary complex with recruited E3 ligases. This complex formation affects the degradation ability of TPD molecules, and thus we tested for visualization of the intracellular dynamics of ternary complex formation. In this study, we applied the fluorescent-based technology detecting protein-protein interaction (Fluoppi) system, in which detectable fluorescent foci are formed when ternary complex formation induced by TPD molecules occurs in cells. We show here that cells coexpressing BRD4 and cereblon (CRBN) tagged with the Fluoppi system formed detectable foci in both live and fixed cells only when treated with BRD4-targeting degraders utilizing CRBN as an E3 ligase in dose- and time-dependent manners. Notably, the maintenance and efficacy of TPD molecule-induced foci formation correlated with the ability to degrade target proteins. Furthermore, we demonstrated that BRD4-targeting and FKBP12F36V-targeting degraders formed ternary complexes mainly in the nucleus and cytoplasm, respectively, suggesting that TPD molecules utilize the proteasome to degrade target proteins in their corresponding localized region. Our results also suggest that the Fluoppi system is a powerful tool for characterizing TPD molecules by visualizing the spatiotemporal formation of ternary complex.

Virus infection induces the development of T follicular helper (TFH) and T helper 1 (TH1) cells. Although TFH cells are important in anti-viral humoral immunity, the contribution of TH1 cells to a protective antibody response remains unknown. We found that IgG2 antibodies predominated in the response to vaccination with inactivated influenza A virus (IAV) and were responsible for protective immunity to lethal challenge with pathogenic H5N1 and pandemic H1N1 IAV strains, even in mice that lacked TFH cells and germinal centers. The cytokines interleukin-21 and interferon-γ, which are secreted from TH1 cells, were essential for the observed greater persistence and higher titers of IgG2 protective antibodies. Our results suggest that TH1 induction could be a promising strategy for producing effective neutralizing antibodies against emerging influenza viruses.

Memory CD4+ T cells promote protective humoral immunity; however, how memory T cells acquire this activity remains unclear. This study demonstrates that CD4+ T cells develop into antigen-specific memory T cells that can promote the terminal differentiation of memory B cells far more effectively than their naive T-cell counterparts. Memory T cell development requires the transcription factor B-cell lymphoma 6 (Bcl6), which is known to direct T-follicular helper (Tfh) cell differentiation. However, unlike Tfh cells, memory T cell development did not require germinal center B cells. Curiously, memory T cells that develop in the absence of cognate B cells cannot promote memory B-cell recall responses and this defect was accompanied by down-regulation of genes associated with homeostasis and activation and up-regulation of genes inhibitory for T-cell responses. Although memory T cells display phenotypic and genetic signatures distinct from Tfh cells, both had in common the expression of a group of genes associated with metabolic pathways. This gene expression profile was not shared to any great extent with naive T cells and was not influenced by the absence of cognate B cells during memory T cell development. These results suggest that memory T cell development is programmed by stepwise expression of gatekeeper genes through serial interactions with different types of antigen-presenting cells, first licensing the memory lineage pathway and subsequently facilitating the functional development of memory T cells. Finally, we identified Gdpd3 as a candidate genetic marker for memory T cells.

High harmonic generation (HHG) in solids has great potential for coherent extreme ultraviolet (EUV) sources, all-optical band-structure reconstruction, and electron dynamics metrology. Solid HHG driven by plasmonic near-fields will open a new paradigm, enabling high repetition-rate HHG with a compact laser, HHG manipulation with meta-surfaces, and precise control over carrier trajectory. In this paper, we demonstrate antenna-enhanced HHG in a wide-bandgap semiconductor ZnO. By exploiting gold nano-antennas resonating at the driver wavelength of 2 μm, we successfully trigger HHG at input intensity of ~0.02 TW/cm2 and observe harmonic radiations up to 9th-order. Orders-of-magnitude enhanced conversion efficiency at the hot-spots brings about ten-fold enhancement in the total yield. The spectral selection rule is found to reflect crystal symmetry, suggesting the possibility of nano-scaled EUV sources and band-structure reconstruction.

The polarization property of high harmonics from gallium selenide is investigated using linearly polarized midinfrared laser pulses. With a high electric field, the perpendicular polarization component of the odd harmonics emerges, which is not present with a low electric field and cannot be explained by the perturbative nonlinear optics. A two-dimensional single-band model is developed to show that the anisotropic curvature of an energy band of solids, which is pronounced in an outer part of the Brillouin zone, induces the generation of the perpendicular odd harmonics. This model is validated by three-dimensional quantum mechanical simulations, which reproduce the orientation dependence of the odd-order harmonics. The quantum mechanical simulations also reveal that the odd- and even-order harmonics are produced predominantly by the intraband current and interband polarization, respectively. These experimental and theoretical demonstrations clearly show a strong link between the band structure of a solid and the polarization property of the odd-order harmonics.

High harmonic generation (HHG) in a ZnO single crystal is driven by the enhanced near-fields of resonant nanoantennas. Non-perturbative HHG into deep-UV range is successfully induced by optical excitation of as low as 20 GW/cm2. The spectral selection rule is found to reflect crystal symmetry, suggesting the possibility of nano-scaled EUV sources and band-structure reconstruction.

We have developed an ab-initio simulation for high-order-harmonic generation from bulk GaSe. The simulation shows even-order harmonics are exclusively generated from the interband current while odd-order ones are dominated by intraband current below the band-gap.

Germinal centers (GCs) are generally considered to be the sole site of memory B-cell generation. However, recent studies demonstrate that memory B cells can also develop in response to a T-cell dependent (TD) antigen before the onset, and independently of, the GC reaction. These two classes of memory cells persist equally over long periods of time and attain functional maturation through distinct but related transcriptional programs. Although the development of both memory B-cell types requires classical T-cell help, the generation of GC-dependent memory B cells requires TFH -cell help, while the generation of GC-independent memory cells does not. These findings led to the conclusion that B-cell memory is generated along two fundamentally distinct cellular differentiation pathways. In this review, we focus on the GC-independent pathway of memory B-cell development, and discuss how the unique features of memory B cells are maintained in the GC-independent pathway.

SummaryMemory B cells are essential for generating rapid and robust secondary antibody responses. It has been thought that the unique cytoplasmic domain of IgG causes the prompt activation of antigen-experienced IgG memory B cells. To assess this model, we have generated a mouse containing IgG1 B cells that have never encountered antigen. We found that, upon challenge, antigen-experienced IgG1 memory B cells rapidly differentiated into plasma cells, whereas nonexperienced IgG1 B cells did not, suggesting the importance of the stimulation history. In addition, our results suggest that repression of the Bach2 transcription factor, which results from antigen experience, contributes to predisposition of IgG1 memory B cells to differentiate into plasma cells.

Infection with single strand RNA (ssRNA) viruses, such as influenza A virus, is known to induce protective acquired immune responses, including the production of neutralizing antibodies. Vaccination also causes a reduction in the number of peripheral blood leukocytes (PBL) shortly after inoculation, a result which may have undesirable adverse effects. The cellular mechanisms for this response have not been elucidated so far. Here we report that formalin-inactivated influenza A whole virus vaccine (whole virion) induces a significant decrease in PBL in mice 5–16 h after administration, whereas an ether-split vaccine (HA split) made from the same influenza virus strain does not induce a similar loss of PBL. Concordant with this reduction in the number of PBL, a rapidly induced and massive production of interferon (IFN)-α is observed when mice are injected with whole virion, but not with HA split vaccines. The role of Toll-like receptors (TLR), which are involved in signal transduction of influenza virus, and the subsequent induction of IFNα were confirmed using mice lacking TLR7, MyD-88, or IFNα/β receptor. We further demonstrated that the observed PBL loss is caused by apoptosis in an IFNα-dependent manner, and not by leukocyte redistribution due to chemokine signaling failure. These findings indicate that RNA-encapsulated whole virion vaccines can rapidly induce a loss of leukocytes from peripheral blood by apoptosis, which may modulate the subsequent immune response.

Maternal separation (MS) is known to affect hippocampal function such as learning and memory, yet the molecular mechanism remains unknown. We hypothesized that these impairments are attributed to abnormities of neural circuit formation by MS, and focused on brain-derived neurotrophic factor (BDNF) as key factor because BDNF signaling has an essential role in synapse formation during early brain development. Using rat offspring exposed to MS for 6 h/day during postnatal days (PD) 2-20, we estimated BDNF signaling in the hippocampus during brain development. Our results show that MS attenuated BDNF expression and activation of extracellular signal-regulated kinase (ERK) around PD 7. Moreover, plasticity-related immediate early genes, which are transcriptionally regulated by BDNF-ERK signaling, were also reduced by MS around PD 7. Interestingly, detailed analysis revealed that MS particularly reduced expression of BDNF gene and immediate early genes in the cornu ammonis 1 (CA1) of hippocampus at PD 7. Considering that BDNF-ERK signaling is involved in spine formation, we next evaluated spine formation in the hippocampus during the weaning period. Our results show that MS particularly reduced mature spine density in proximal apical dendrites of CA1 pyramidal neurons at PD 21. These results suggest that MS could attenuate BDNF-ERK signaling during primary synaptogenesis with a region-specific manner, which is likely to lead to decreased spine formation and maturation observed in the hippocampal CA1 region. It is speculated that this incomplete spine formation during early brain development has an influence on learning capabilities throughout adulthood.

Signals through BCR and costimulatory molecules play essential roles in selecting high-affinity B cells with Ig V-region mutations in the germinal centers (GCs) of peripheral lymphoid organs. Lyn-deficient (lyn−/−) mice show impaired BCR signal triggering for cell proliferation and GC formation, causing hyper-IgM, and display autoimmunity after aging. In this study, we demonstrate that Lyn-mediated signaling to upregulate GANP is essential for the survival of mature GC-like (mGC) B cells with high-affinity type BCR mutations upon Ag immunization. Transgenic ganp expression into lyn−/− mice did not recover the Lyn-deficient phenotype with regard to B cell differentiation, serum Igs, and impaired GC formation in spleens after immunization with nitrophenyl-chicken γ-globulin, but it markedly rescued cell survival of mGC B cells by suppressing DNA damage, thereby increasing the frequency of the Trp33-to-Leu mutation in the IgVH-186.2 region and affinity maturation of nitrophenyl-binding B cells. GANP may play a critical role in Lyn-mediated signaling for the selection of high-affinity B cells in peripheral lymphoid organs.

B cell memory is generated along two fundamentally distinct cellular differentiation pathways., One component of memory in the antibody system is long-lived memory B cells selected for the expression of somatically mutated, high-affinity antibodies in the T cell–dependent germinal center (GC) reaction. A puzzling observation has been that the memory B cell compartment also contains cells expressing unmutated, low-affinity antibodies. Using conditional Bcl6 ablation, we demonstrate that these cells are generated through proliferative expansion early after immunization in a T cell–dependent but GC-independent manner. They soon become resting and long-lived and display a novel distinct gene expression signature which distinguishes memory B cells from other classes of B cells. GC-independent memory B cells are later joined by somatically mutated GC descendants at roughly equal proportions and these two types of memory cells efficiently generate adoptive secondary antibody responses. Deletion of T follicular helper (Tfh) cells significantly reduces the generation of mutated, but not unmutated, memory cells early on in the response. Thus, B cell memory is generated along two fundamentally distinct cellular differentiation pathways. One pathway is dedicated to the generation of high-affinity somatic antibody mutants, whereas the other preserves germ line antibody specificities and may prepare the organism for rapid responses to antigenic variants of the invading pathogen.

Resting antigen-experienced memory B cells are thought to be responsible for the more rapid and robust antibody responses after antigen reencounter, which are the hallmark of memory humoral responses. The molecular basis for the development and survival of memory B cells remains largely unknown. We report that phospholipase C (PLC) γ2 is required for efficient formation of germinal center (GC) and memory B cells. Moreover, memory B cell homeostasis is severely hampered by inducible loss of PLC-γ2. Accordingly, mice with a conditional deletion of PLC-γ2 in post-GC B cells had an almost complete abrogation of the secondary antibody response. Collectively, our data suggest that PLC-γ2 conveys a survival signal to GC and memory B cells and that this signal is required for a productive secondary immune response.

We established a two-dimensional electrophoresis (2-DE) mapping database of splenic CD4 T cells prepared from I-A d -restricted ovalbumin (OVA) 3 2 3 - 3 3 9 specific T cell receptor (TCR) transgenic mice (OVA23-3). First we examined the purification of CD4 T cells and found that the high purity of cells produced more accurate protein maps. The first dimension utilized narrow-range immobilized pH gradients (IPGs), pH 4.0-5.0, pH 4.5-5.5, pH 5.0-6.0, and pH 5.5-6.7. Approximately 1300 spots were detected by silver staining. Detection was performed by in-gel tryptic digestion of the spots, matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) technology and database searches via the world wide web (WWW). We have so far identified 255 proteins on 2-DE gels of whole cell lysates. This is the first construction of a proteome database for murine unsensitized CD4 T lymphocytes. To examine this further, 2-DE mapping was utilized for splenic CD4 T cells from another TCR transgenic mouse strain (DO11.10 TCR transgenic mice). Mapping patterns were found to be almost identical to those from CD4 T cells from OVA23-3 mice. These results indicated that the 2-DE maps in this study could be used for mouse CD4 T cells to examine protein changes in cells given certain stimuli.

The oral administration of antigen can lead to systemic antigen-specific hyporesponsiveness, also known as oral tolerance. This phenomenon is a representative form of immune tolerance to exogenous antigen under physiological conditions. We have previously reported that long term feeding of dietary antigen to ovalbumin-specific T cell receptor (TCR) transgenic mice induced oral tolerance of peripheral T cells with impairment in their TCR-induced calcium-signaling pathway. In this study, we utilized two-dimensional electrophoresis to compare intracellular protein expression patterns of orally tolerant and unsensitized CD4 T cells. We detected 26 increased and 16 decreased protein spots and identified 35 of these by mass spectrometry. The results indicated that the expression of caspases was up-regulated and that the protein levels of intact proteins susceptible to caspase cleavage, such as Grb2-related adaptor downstream of Shc (GADS), were decreased in orally tolerant CD4 T cells. Western blotting experiments confirmed that expression of the active form of caspase-3 and the antiapoptotic factor, X-linked inhibitor of apoptosis, were both up-regulated in orally tolerant CD4 T cells, which were found to be nonapoptotic. We further demonstrated that orally tolerant CD4 T cells could not form normal TCR signaling complexes associated with GADS and showed down-regulated phospholipase C-gamma1 activation, which is likely to contribute to the impairment of TCR-induced calcium signaling. Our findings indicate that orally tolerant CD4 T cells up-regulate caspase activation and show decreased levels of caspase-targeted proteins, including TCR signaling-associated molecules, while up-regulating antiapoptotic factors, all of which appear to contribute to their unique tolerant characteristics.

In some neurological disorders, excessive nitric oxide (NO, nitrogen monoxide) produced by inducible and/or neuronal nitric oxide synthases (iNOS and nNOS) is able to combine with superoxide (O(minus sign)(2)) to form peroxynitrite (ONOO(minus sign)), which can then induce p53-dependent neural apoptosis. In the present study, experiments using p53 knock-out mice primary neural cells revealed that 3-morpholinosydnonimine hydrochloride (SIN-1), a peroxynitrite donor, triggered apoptosis, while p53-transcriptional activity was effectively suppressed in the absence of p53 molecules. This shows that SIN-1 was able to induce p53-dependent apoptosis in murine primary neural cells. The mechanism responsible for the SIN-1-induced accumulation of p53 molecules was then analyzed. Western blot analysis indicated that p53 accumulation caused by SIN-1 did not require p53 phosphorylation, whereas SIN-1 treatment triggered MAP kinase (MAPK) phosphorylation and pretreatment with the MAP kinase kinase (MEK) inhibitor U0126 inhibited p53 accumulation. Pretreatment of the neural cells with lovastatin, an inhibitor of p21(ras) signaling, greatly inhibited the accumulation of p53 induced by SIN-1. Northern blot and immunofluorescence analyses revealed that primary neural cells treated with SIN-1 had increased levels of p19 alternate reading frame (p19(ARF)) mRNA and protein, which is induced by MAPK and stabilizes the p53 protein. Our findings clearly show that the p21(ras)-MAPK-p19(ARF) pathway has an essential role in p53-dependent apoptosis triggered by peroxynitrite in neural cells.

In the mammalian central nervous system, a complexcircuit of neurons contributes to higher behaviors.Each region of the brain has a unique function derivedfrom various types of neurons. Several neuralprecursor cell lines have been established from basalganglia of fetal brain. In this study, hippocampalneural precursor cell lines were established from thehippocampus of p53-/- embryos. By means ofintegration of a MycER regulatable oncoprotein intop53-/- neural precursor cells, several immortallines were established from embryonic hippocampalprimordium, with bFGF and estrogen continuouslysupplied for activation of the MycER protein. A dualluciferase study demonstrated that the MycER proteinblocked the expression of a glial cell marker protein,GFAP, probably contributing to the persistent celldivision of the immortalized neural precursor cells.These cell lines differentiate into neuronal and glialcell types after withdrawal of bFGF. The phenotype ofthe hippocampal cell lines differed from that of thebasal ganglia cell lines as observed in a clonaldensity culture. This result implies that each regionof the brain has a unique developmental program, thatmay be imprinted in each of the neural precursor cells.

High-affinity memory B cells are preferentially selected during secondary responses and rapidly differentiate into antibody-producing cells. However, it remains unknown whether only high-affinity, mutated memory B cells simply expand to dominate the secondary response or if in fact memory B cells with a diverse VH repertoire, including those with no mutations, accumulate somatic mutations to create a new repertoire through the process of affinity maturation. In this report, we took a new approach to address this question by analyzing the VH gene repertoire of IgG1+ memory B cells before and after antigen re-exposure in a host unable to generate IgG+ B cells. We show here that both mutated and unmutated IgG1+ memory B cells respond to secondary challenge and expand while accumulating somatic mutations in their VH genes in a stepwise manner. Both types of memory cells subsequently established a VH gene repertoire dominated by two major clonotypes, which are distinct from the original repertoire before antigen re-exposure. In addition, heavily mutated memory B cells were excluded from the secondary repertoire. Thus, both mutated and unmutated IgG1+ memory cells equally contribute to establish a new antibody repertoire through a dynamic process of mutation and selection, becoming optimally adapted to the recall challenge.

The viral protein Nef is a key element for the progression of HIV disease. Previous in vitro studies suggested that Nef expression in T-cell lines enhanced TCR signaling pathways upon stimulation with TCR cross-linking, leading to the proposal that Nef lowers the threshold of T-cell activation, thus increasing susceptibility to viral replication in immune response. Likewise, the in vivo effects of Nef transgenic mouse models supported T-cell hyperresponse by Nef. However, the interpretation is complicated by Nef expression early in the development of T cells in these animal models. Here, we analyzed the consequence of Nef expression in ovalbumin-specific/CD4(+) peripheral T cells by using a novel mouse model and demonstrate that Nef inhibits antigen-specific T-cell proliferation and multiple functions required for immune response in vivo, which includes T-cell helper activity for the primary and memory B-cell response. However, Nef does not completely abrogate T-cell activity, as defined by low levels of cytokine production, which may afford the virus a replicative advantage. These results support a model, in which Nef expression does not cause T-cell hyperresponse in immune reaction, but instead reduces the T-cell activity, that may contribute to a low level of virus spread without viral cytopathic effects.

Although Escherichia coli LPS is known to elicit various proinflammatory responses in macrophages, its effect on the translational states of transcripts has not yet been explored on a genome-wide scale. To address this, we investigated the mRNA profiles in polysomal and free messenger ribonucleoprotein particle (mRNP) fractions of mouse macrophage-like J774.1 cells, using Affymetrix Mouse Genome 430 2.0 GeneChips. Comparison of the mRNA profiles in total cellular, polysomal, and free mRNP fractions enabled us to identify transcripts that were modulated at the translational level by LPS: among 19,791 transcripts, 115 and 418 were up- and downregulated at 1, 2, or 4 h after LPS stimulation (100 ng/ml) in a translation-dependent manner. Interestingly, gene ontology-based analysis suggested that translation-dependent downregulated genes frequently include those encoding proteins in the mitochondrial respiratory chain. In fact, the mRNA levels of some transcripts for complexes I, IV, and V in the mitochondrial respiratory chain were translationally downregulated, eventually contributing to the decline of their protein levels. Moreover, the amount of metabolically labeled cytochrome oxidase subunit Va in complex IV was decreased without any change of its mRNA level in total cellular fraction after LPS stimulation. Consistently, the total amounts and activities of complexes I and IV were attenuated by LPS stimulation, and the attenuation was independent of nitric oxide. These results demonstrated that translational suppression may play a critical role in the LPS-mediated attenuation of mitochondrial oxidative phosphorylation in a nitric oxide-independent manner in J774.1 cells.

We examined intracellular signaling of hyporesponsive CD4 T cells induced by continuous feeding with high-dose antigen in a TCR transgenic mouse system. The results demonstrated a selective impairment in their TCR-induced calcium/NFAT-signaling pathway. Proteomic analysis revealed caspase activation in these cells, which resulted in cleavage of GADS. Further analysis of the TCR-signaling complex showed that GADS-LAT-SLP-76-associated PLC-gamma1 was decreased in both phosphorylation and association. Thus, as a consequence of caspase activation, orally tolerant CD4 T cells could not form normal TCR signaling complexes associated with GADS and showed downregulated PLC-gamma1 activation, which resulted in impairment of TCR-induced calcium signaling.

Chaetomellic anhydride A, a potent inhibitor of Ras protein farnesyltransferase, was synthesized in 61% yield over four steps from methyl propionate. The synthesis features palladium-catalyzed carboxylation reaction under Cacchi conditions, efficiently incorporating carbon monoxide generated in situ from acetic formic anhydride into β-carbomethoxyalkenyl triflate, and giving rise to the maleic anhydride motif of chaetomellic anhydride A. Noteworthy is the remarkable reactivity of the carboxylation reaction that takes place at room temperature despite the fact that common palladium-catalyzed carboxylations generally require rather harsh conditions. The scope of the method is also presented.